Self propelled, engine driven, riding mowers have been in use for several decades. In the last twenty .years evolution has stabilized to provide the domestic lawn mower, mowers with the cutters forward of carriage wheels, cutters trailing carriage wheels, and specialized mowers such as those on booms extending from wheeled carriages. Domestic lawn mowers are ideally suited to small tracts having gradual grade changes but they cannot negotiate rough terrain to gain access to areas suitable for their operation. Mowers with the cutters ahead of the carriage wheels have no peers for maneuverability and work well around trees in parkways and the like. They do require constant operator attention to terrain changes. They do not negotiate rough terrain very well, especially with cutters suspended rather than riding on limiter skids that prevent scalping turf, Mowers with the cutters trailing the carriage are awkward for the operator to observe and they will negotiate rough terrain for access to operational areas, they endanger operators and observers that the operator cannot constantly monitor, Additionally, they have evolved around the common agricultural tractor which is commonly quite heavy compared with a carriage required to manage the mowing machinery. Further, the massiveness of the tractor requires a robust cutter frame to withstand the inevitable impact involving the tractor inertia, Specialized mowers serve a purpose in mowing areas no carriage can access and, if there, could not operate because of congestion and severe grade change. They are small area necessities.
The mower construction art has evolved to usually define mower structure with at least one vertical spindle carrying a cutter blade in a rigid housing as a mower deck, therefore, that definition will be used herein and the mower assembly hingedly connecting three rigid, blade carrying, cutter decks will be regarded as an assembly of three independent decks. The upper plane of a deck is generally above and parallel to the mowed plane.
There is a need for a mowing machine that will negotiate terrain too rough for mowing operation yet work efficiently on large areas once accessed. For overall economic reasons the, entire machine needs a balanced concept providing self-propelled transport with cutter and carriage ruggedized only to the extent the purpose requires. Additionally, the drive system for all powered components needs simplification rather than adaptation of existing systems not ideally suiting the purpose.
It is therefore an object of this invention to provide a mowing machine with a carriage suitable for on-road and off-road self transport, with a high lift cutter system that will fold to legal width for road transport.
It is another object of this invention to provide a mowing machine with a simplified drive system for both mowing machinery and the carriage, with easy maintainability, that is usable on reasonably rough terrain.
It is still a further object of this invention to provide hinged assembly of mower decks to permit a wide cutting swath to generally follow rolling terrain.
It is yet another object of this invention to provide a mowing machine with a hinged assembly of mower decks that will tilt at the hinges while keeping the cutter blades above the cutting plane of a selected deck.
It is still another object of this invention to provide mower cutting blades with the tips upturned with a radius that originates at the center of rotation of hinges that control the tilting movement of the tilted deck structure.
These and other objects, advantages, and features of this invention will be apparent to those skilled in the art from consideration of this specification, including the attached claims and appended drawings